Fact: people like me spend way too much worrying about how lineups are arranged. Simulations suggest that only the worst lineups, ones that even Dusty Baker would never conceive of, have a real impact on run scoring. The difference between what a major league manager would typically run out there and a supposed optimal lineup isn’t usually very signifcant.

Don Mattingly said Dee Gordon was his leadoff man and Kemp would bat third, but that the rest of the lineup is not yet fully decided. Mattingly said [Andre] Ethier would likely hit cleanup against right-handed pitchers and that Juan Rivera could hit cleanup against lefties. Mattingly said Mark Ellis will get the first shot at batting second, though Mattingly wouldn’t mind James Loney or even [Jerry] Sands hitting in the second spot in the lineup.

How can it be a good idea to stick maybe the NL’s best RBI guy immediately behind Gordon and Ellis? Gordon had a .325 OBP in 224 at-bats after arriving in the majors last season. Ellis came in at .288 in 480 at-bats with the A’s and Rockies.

Kemp is going to be stepping up to the plate with none on and two out an awful lot in this scenario.

If Kemp has to come up with none on, it’s much better that he does it with none out in the inning. That’s part of why hitting him fourth makes so much more sense. If Kemp is batting fourth and he bats in the first inning, he’s guaranteed to have at least one man on base. If he has to wait until the second, then that’s a better chance the Dodgers are going to have of scoring in the second inning.

Want a little evidence? National League No. 3 and No. 4 hitters were practically identically productive last season. No. 3 hitters hit .280/.353/.457, while No. 4 hitters came in at .269/.352/.455.

No. 3 hitters, though, averaged .127 RBI per plate appearance, while cleanup hitters came in at .139 RBI per plate appearance. No. 4 hitters get to hit behind better hitters, for the most part.

Plus, the Dodgers lineup actually sets up better with Ethier hitting third and Kemp batting fourth. Mattingly is going to want Loney hitting fifth against right-handers, and if Ethier hits cleanup, that puts lefties back-to-back. That’s why Kemp was the Dodgers cleanup hitter last year until Ethier went down.

Of course, Kemp, already an MVP candidate before Ethier was hurt, performed even better after moving into the third slot. I’m sure that’s what’s on Mattingly’s mind here. That and getting him those extra two or three plate appearances every month. But I think Mattingly had the right idea last year.

Jon Heyman of FanRag Sports reports Thursday that the Orioles “are said to have begun fielding calls of interest” on superstar Manny Machado and “are close to the point of seriously weighing whether to trade him.”

You’d think it would be a no-brainer for the last-place O’s to flip Machado — an impending free agent — for prospects, but Heyman notes there is “still a question whether or not longtime Orioles owner Peter Angelos” will give the go-ahead. One person familiar with the situation put it a “50-50” likelihood. Another suggested that it would take a massive return, which, sure.

Machado entered play Thursday with a sensational .328/.405/.635 batting line, 15 home runs, and an MLB-leading 43 RBI in 49 games. It’d be a real shock if he’s still wearing an O’s uniform by the end of July.

Heyman reported previously that at least nine teams made aggressive plays for Machado this winter, including the Cubs, Phillies, Dodgers, Indians, Diamondbacks, Yankees, Red Sox, White Sox, and Cardinals. A whole lot of those teams still make sense here in late May — maybe all of them except the White Sox.